In this video segment adapted from A Science Odyssey, learn what led British researcher Alexander Fleming to the chance discovery of antibacterial properties of a mold extract he later named penicillin. After treating World War I battlefield casualties, Fleming began searching for compounds that would ward off infections in humans. Returning from vacation in the summer of 1928, he noticed that mold was partly covering one of the agar plates in which he had been growing bacteria, and that the mold inhibited bacterial growth. Fleming determined that the mold possessed properties that could kill bacteria cells without harming human blood cells.
This media asset was adapted from the A Science Odyssey: Matters of Life and Death.
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